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Japan, 2093. A rural town that used to be the most prestigious town in the world has long since sunk 30 meters under the ocean's surface. The story is a tale of a girl who takes part in free diving (diving without the aid of equipment to breathe), and the emotional growth she experiences.
Ganbare, a black fish born into a shoal of red fish, tries to fit in amid adventures as he is chased by tuna and must evade the Great Octopus.
Miku Hatsune slowly descends into the ocean, staring up at the beauty above...